package day6;

import java.io.File;

public interface My {
    //公开的 静态的 常量
    //public static final
    String name="a";
}
class My2{
    public void test() {
        System.out.println(My.name);
        byte n1 = 127; //-128 -127
        short n2 = 2;
        int n3 = 3;
        long n4 = 2147000000; //没有超过int 不用加l
        long n5 = 2147800000l; //超过范围 认为long  必须加l
        float f1 = 10.0f;
        double f2 = 20.0;
        Long l1 = 10l; //封装类型  必须强制加符号
        Float l2 = 10f;
        Double l3 = 10d;
        File f = new File("c://");
        int[] nums = {};
        int[][] nums2 = new int[3][2];
        int[][] nums3 = new int[3][];
        /*int[][] nums4=new int[][2];
        {{},{},{}}*/
        int[][] newArray;
        int[] newArray2[] = new int[3][2];
        int newArray3[][];
        newArray2[1][2] = 10;
    }
}
